This is a "brand new" precision collet chuck holder for and hobbyists demanding. Collet must be assembled into the clamping nut before inserting into the chuck. Ease of operation and high quality work results. Specifications Model: R8-ER32 R8 spindle Drawbar thread: 7/16 ER32 clamping range: 1-20mm Spanner/wrench1X 45-52 Suitable For: R8 dedicated machine so far. Color: Silver+black Material: metal Size: 16cm/6.3 inch Package Contents: 1 x set of milling chuck extension bar Note 1. Before using this tool, please measurement tool deflection, tool deflection accuracy exceeds 0.01MM, please correct before cutting. 2. The tool extends the length of the chuck as short as possible, the tool extends the amount of time longer if extended, please cut their own speed, feed rate or cutting the amount. 3. If the cutting of abnormal vibration or sound, cut spindle speed and depth of cut to improve the situation Only the above package content, other are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.